This invention is concerned with fluorescent lighting systems and particularly with techniques for maximizing the efficiency of such systems, i.e., providing a maximum amount of light output as a function of the amount of electrical power which is input to the fluorescent lamp.
It is well known that the efficiency and reliability of a fluorescent lamp can be affected by the characteristics of the electrical power which is used to drive the lamp. Thus many techniques have been disclosed in the prior art for controlling the electrical input to such a lamp while achieving a high efficiency concurrent with maintaining long lamp life and safe and reliable operation. Davenport and Duffy (Current Interrupt System, Journal of the Illuminating Engineering Society, Volume 18, Pages 3-8 (1989)), for example, achieved improvements in the efficiency of fluorescent lamps by using transient overvoltage and subsequent current interruption as a means of ballasting. The discharge was fully interrupted, with zero voltage and current between imposed voltage transients.